Many scenarios in the field of computing, and particularly on the worldwide web, involve the preparation of a set of content items, such as new stories, articles, data sets, media objects, and applications. A source of a content item set (e.g., a generator, aggregator, or distributor of such content items) may provide public access to at least a portion of the content item set, but may endeavor to recoup the costs of the provision. In some scenarios, the costs may be recouped by charging requesters to access some content items (either on a per-item basis or as a subscription to the content item set) or by providing a limited version of a content item to the requester and offering to provide a full version of the content item upon receiving payment from the requester. A “micropayment” system may also be implemented to encourage a steady stream of small payments from users. In other scenarios, the content provider may recoup the costs of the provision from advertisers, and may enable advertisers to deliver advertisements to the requesters in relation to the requests for the content items (e.g., by embedding an advertisement in the content item.) In still other scenarios, the content provider may offer value-added services in relation to the content items, and may advertise the value-added services to requesters while presenting the related content items. The revenue from such techniques may be used to sustain the provision of the service to the public.